Bug 26033: Use pic.infini.fr instead of framapic

Bug 26033: Use pic.infini.fr instead of framapic

https://framapic.org/ is closing
"""
Framapic will be closing its doors on Tuesday, January 12, 2021. You will find a similar service on this page.
Uploading images is now disabled, but you can still retrieve your images on the My images page.
"""

https://framablog.org/2019/09/26/lets-de-frama-tify-the-internet/
https://framablog.org/2020/03/03/10-bonnes-raisons-de-fermer-certains-services-framasoft-la-5e-est-un-peu-bizarre/
(French)

We can still use another service. However we may think about hosting the
service ourself!

Test plan:
Modify a selenium script to make it fail (for instance modify the path
for a find_element call)
Run it
Confirm that the screenshot has been uploaded correctly and that the
link works

Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>